The present disclosure relates to a memory controller, and particularly to a memory controller that performs a substitution process on a memory in which an error has occurred, a storage apparatus, an information processing system, and a control method therefor.
A storage apparatus including a non-volatile memory and a memory controller has been used widely. The non-volatile memory performs an access operation in a unit of page of a plurality of bytes, and the memory controller controls the non-volatile memory. In the past, as such a storage apparatus, a storage apparatus in which a memory controller performs a substitution process in a unit of page when a page in which an error associated with memory accessing has occurred (error page) is substituted has been known.
However, as the capacity of the non-volatile memory increases, the number of pages contained therein also increases. Therefore, the number of entries of substitution management information that is necessary for the substitution process increases, and the size of the substitution management information increases. Accordingly, there has been a problem of an increased burden of the substitution process.
In this regard, for example, a storage apparatus in which a memory is managed in segments including a plurality of access units (pages in the above-mentioned example) and the substitution process is performed in a unit of segment has been proposed (see, for example, Japanese Patent Application Laid-open No. 2003-323352).